Preselector



Patented, June 6, 1939 i UNITED STATES,

PATENT OFFICE 'PRESELECTOB Edward I. Ma'stney. Berwyn, 111., assignor to Oak Manufacturing Company, Chicago, 211., a cor- I poration of Illinois Application January 21, less, Serial No. 187,180

' 16 Claims. (01. 74-40) gears are each provided with a finger or other 10 means extending toward each other. Between these gear fingers, an adjustable finger, ordinarily rigid with respect to an operating shaft, is adapted to be turned to a predetermined position. Such a device finds ready application for 15 use in connection with radio-receivers or similar devices wherein it is desired to turn a shaft to one of a definite number of predetermined positions.

Since most radio receivers are tuned by gang condensers, and since such gang condensers are operative as a rule over a range of 180 degrees, it is clear that a preselector should preferably be capable of operating over thi'se'ntire range.

While in practice the full 180 degrees on a radio receiver is rarely used as far as a choice of de- 25 sirable stations isconcerned, nevertheless, it may be desirable as a selling feature to provide full 180 degree operation. The device of Ten Cate is adapted to operate over a region of 180 degrees minus one-half the angle subtended by the finger 30 which is rigidly coupled to the shaft. While this angle may be made small it nevertheless represents a departure from a desired 189 degrees. An object of this invention is to'improve upon this construction so that a full 180 degree opera- 5 tion, and even more if desired, may be secured. An additional object is to simplify and improve the mechanism disclosedin the above application. A more general object is to provides, preselector which is simple, cheap, compact and 40 easily operated. Other and additional objects will appear in connection with the description. Referring to the drawing:

Figure 1 shows an elevation partly in section of the preselecting mechanism, with the shaft 45 and sleeve in section.

' Figure 2 is a side view of a preselector-un.itin a normal position. a Figure 3 shows the mechanism in the depressed position after the unit has been operated upon 50 and before the spring returns it to its normal- Figure 6 is a detail of a sleeve.

Any suitable mechanism upon which the preselectingrmeans may operate may be used and in this particular case, Figure lshows a gang condenser l having a shaft H, the entire con- 5 structionznounted upon a base 82. Shaft ii is provided with any-suitable universal joint $3 I which is coupled to the preselector shaft 85 supported by side plates l6 and ll extending upwardly in. spaced relation from base t2. Shaft 10 i5 is preferably cut away at; opposite portions to provide flats i8 and i9. shaft 115 is adapted to have a plurality of separately adjustable preselector units and, since all of them are the same, only one will be described in detail. Thus, one w preselector unit comprises a pair of sleeves 2d and 2| disposed over shaft it. Sleeve 2% has a reduced portion 22, while sleeve 2 I has a similarly reduced portion 23, both the said portions facing each other. As clearly indicated in the section 20 of one unit in Figure 1 and also in Figure 6 each sleeve has a cylindrical bore tofit shaft but has its reduced end provided with a non-circular aperture 24. Each sleeve is therefore rotatively locked to shaft l5 but movable longitudinally 25 thereof.

Between sleeves and 2| a washer is disposed havlng a circular aperture 26 and a finger 21 extending outwardly therefrom. Washer 25 is freely rotatable around shaft IE, but the aperbe described in detail later. so

Disposed on each side of washer 25 and freely rotatable around reduced portions 22 and 23 of the sleeves, are sleeve washers 30 and 3! respectively. Both washers are provided with apertures 32 and as and bent flngers 34 and at. These as washers are identical and are so disposed that fingers 34 and 35 point inwardly toward center washer 25. As is clearly evident in Figure 4, fingers-34 and 35 extend over just farenough to hem the path of movement of finger 2? of so the center washer.

On each side of sleeve washers 30 and ii are gears 40 and 4| having apertures $2 and as. equal in size to apertures 32 and 33 of washers 30 and 3|. These gears are also freely rotatable M around the reduced portions of sleeves 20 and 2 l. The length of the reduced portions of sleeves 2d and 25 is so adjusted with respect to the com- 'bined thickness of all of the gears and washers of each unit that when the sleeves are jammed together to grip washers 25, the gears and sleeve washers will just freely turn around the sleeves and have a minimum of side play.

Gears id and ii are identical in all respects and as shown are'provided with gear teeth it and -25 extending for almost the entire circumference of the gear.' However, the angle corresponding to several of the teeth, in this instance approximately three teeth, is taken up by solid tongues Bit and 5 1 which terminate in bent fingers dB and id. These fingers, as clearly shown, are bent inwardly at right angles to the plane of the gears just as in the case of the sleeve washers and are just long enough to engage the sides of sleeve washer fingers.

In order to operate each unit; a pair of racks 52 and 53 are provided. These racks have their ends joined by a U-shaped member 5 5 which is provided with a handle 55 and which may carry a knob 5%. Handle 55 extends through slot 58 in a top plate 59 supported by side plates it and ii. Racks 52 and 53 are supported by guide members 52 and 53. These members are suitably slotted and are adapted to maintain racks 52 and 53 in position. Rack 52 is offset from rack 53. In this particular instance, rack 52 is adapted to engage gear M, while rack 531s adapted to engagegear 6%. Since these racks engage gears on opposite sides of the center of rotation, it is clear that these gears will be rotated in opposite directions at equal speeds. Obviously, different sized racks and gears could be used if desired in case unequal speedswere desired. Rack 53 has a finger 65 around which the end of a spring-6d is disposed. The other end of spring 65 is anchored to plate 59. Thus, spring 66 tends to pull up the racks in. the position shown in Figure 2.

When the racks are forced downwardly into the position shownin Figure 3, the gears are rotated in opposite directions and the various fingers are engaged. Thus, gear 40 will turn until its finger ddengages finger 3d of sleeve washer 3d and then both will turn until finger 21 of center washer 25 is engaged. The three of these will turn, assuming that the other gear and sleeve washer have not reached the corresponding position. Assuming this to be the cas, the three will turn until gear ti and washer 3! are encountered by means of their fingers. When fingers 35 and d9 of these elements are encountered, there will be no tendency to turn washer Gear 68 will make almost a complete turn before engaging finger 34 of the adjacent sleeve washer 3B. The difference between 360 degrees.

is due to the angle subtended by washer finger 3 1. Similarly washer 30 will vmake almost a complete turn .before engaging center washer finger 21 on oppositesides thereof. Hence, the

sleeve washer and gear on each side of the center washer together will make almost two complete revolutions before the finger 21 is engaged in traveling from one end' position to the other.

It is clear that center washer 25 may be operated through a much greater angle than 180 degrees by means of the mechanism shown. In practice, it is preferred to adjust the various gears and washers so that in the selected position as shown in Figure 3 center washer 25 has its finger 21 pointing approximately in line with handle 55 of the racks. For operation of a gang condenser where only a 180 degree range is desired, the gears may be adjusted, to the position shown in Figure 2 and the racks 52 and 53 thereupon adjusted to engage said gears. As actually shown, the racks are just large enough and have just enough teeth to operate over a full 180 degrees of range. Hence, for uniformity, all the push buttons 56 will drop to the same bottom position to turn in the desired angle.

Of course, if the condenser shaft or whatever is being operated upon is to have a range greater than 180 degrees, then the racks will be that much longer. In fact, while only one intermediate sleeve washer is provided between each gear and the shaft washer, it is understood that more intermediate sleeve washers may be provided so that a plurality of series operated washers will result, if the range angle is sumciently great. Since each intermediate sleeve washer adds almost 360 degress to the operating range of the shaft washer, as many such additional washers may be provided as may be necessary. Furthermore, it should be understood that while bent fingers have been disclosed as the coupling means between the various mechanical elements, other means may be used. The same remark applies to the gears which may be replaced with pulleys or friction rollers.

In order to adjust the various preselector units shaft 15 is provided with an end bushing 10 suitably shouldered and rigidly mounted thereon so that plate It acts as an abutment for the various sleeves. A movable bushing H is provided to cooperate with side plate l1. Both bushings, of course, are rotatable in their respective side plates. The free end of shaft I5 is threaded at It and extends beyond plate l1. Engaging the threaded end 72 of the shaft is a threaded member ?3 having an enlarged slotted head 74. Member I3 is disposed within a sleeve 15 which bears against bushing H. coupled to flattened shaft 55 but movable lengthwise thereof by having a squared end 17. This sleeve carries a knob it which is suitably apertured to permit slotted head 14 to be concealed therein. In order to maintain a spring pressure on the various sleeve assemblies, a pair of large washers 80 and ill separated by a spring washer 82 is provided between bushing H and the adjacent preselector unit. It is clear that by tightening sleeve 13 by means of a screw driver operating on slotted head 14 that sleeve 15 will be pressed by slotted head it against bushing H and thus tend to pressthe various sleeves of each of the units tightly against each other.

Knob'16 may be turned manually to turn shaft -slip with respect to shaft I5. When the desired station has been tuned in by knob it or the desired shaft position obtained, any preselector unit chosen for that spot has itsbutton 5B depressed to the position shown in Figure 3. Ordinarily,

Member 73 is rotatively 14 while holding knob I6 by the end. In'this.

"means, a second means freely rotatable on said.-

a is desirable to loosen up slotted head 14 just enough so that when push button II is pressed down washer 25 will be forced to the position shown in Figure 3. In other words, the washer should have enough friction against thefends of the sleeves-due to spring 82 so, that no free rotation is possible. In this way, when push button 56- is released, spring 66 will pull the racks back in the position shown in Figure 2 and the various gears and sleeve washerswlll be with-' drawnfrom the center washer 25 without disturbing the position thereof. when another se-v lector is to be adjusted, knob 16 may be turned to a new position. The washer will turn with the shaft while another unit is' being adjusted. In other words, the only time that washer 25 should turn relatively to shaft I5 .is when the mechanism is loosened and when push button 56 has been pressed down to force the washer to turn.

Otherwise sufflcient friction should be maintained so that during subsequentadjustments of other units, the previous adjustments will not be disturbed. After the various preselector units have thus been adjusted, slotted head 14 is tightened against knob 16. This may, be done by means of a screw driver applied to slotted head manner the various preselector units will be ad justed to grip the center washers of each unit.

What is claimed is: 1. A preselector comprising a shaft adapted to be turned to a preselected position, coupling means rotatively adjustable on said shaft, a first means freely rotatable on said shaft on each side of said coupling means, a second means freely rotatable on said shaft on the outer side of each of said first freely rotatable means, means for mechanically engaging each of said second rotatable means to the adjacent first rotatable means after a predeterm'inedangle of rotation dependent upon the relative rotary positions of said various means, means for mechanically engaging eachfirst rotatable means with said coupling means at predetermined angular positions dependent-upon the relative angular pcsitions thereof, and means for simultaneously rotating said second rotatable means in opposite directions.

2. The structure of claim 1 wherein said si multaneously rotating means operates to turn said second rotatable means at equal speeds.

3. A preselector comprising a shaft adapted to be turned to a preselected position, coupling means rotatively adjustable on said shaft, a first means freely rotatable on said shaft on each .side of said coupling means, a gear freely rotatable on said shaft on the outer side of each of said first freely rotatable means, means forimeohanically engaging each gear with the-adjacent first rotatable means after a predetermined angle-of ,rotationdependent upon the relative rotary positions of said gear and said rotatable, means,

means for mechanically engaging each first ro-' tatable/member and said coupling means at predetermined angular positions dependent upon the relative angular positions thereof, and means meshing with 'said gears for simultaneously rotating said gears in opposite directions.

4. A preselector comprising a shaft adapted to be turned to a preselected position, coupling means rotatively adjustable on said shaft, a sleeve on each side of said coupling means longitudinally movable on said shaft but rotatively locked thereto, a first means freely rotatable on each sleeve disposed on each side of said coupling sleeves disposed on the outer side of each of said first freely rotatable means, means for mechani-' cally engaging each of said second rotatable means to the adjacent first rotatable means after a predetermined angle of rotation dependent upon the relative rotary positions of said various, rotatable members, means for mechanically engaging each first rotatable means and said conpling means at predetermined angular positions dependent upon the relative positions thereof,

and means for simultaneously rotating said second rotatable means in opposite directions.

5. The structure of claim 4 wherein each second freely rotatable means comprises a gear.

6. The structure of claim 4 wherein each sleeve is shouldered at the outer end thereof to maintain the two freely rofatable' means against lateral movement.

7. A preselector comprising a shaft adapted to be turned to a preselected position, coupling means including a washer rotatively mounted on said shaft, asleeve on each side of said coupling means rotatively locked to said shaft but moy-.

able longitudinally thereof, a first means freely rotatable on each sleeve disposed on each side of said coupling ineans,a second means freely rotatable on each sleeve disposed on the outer be turned to a preselected position, a washer having an outwardly extending finger rotatively adjustable on said shaft, an additional washer on each side of said first washer, said additional washers being freely rotatable around said shaft and having means engaging said first washer finger at predetermined points, a gear'freely rotatable on the'shaft mounted on each-side of 8. A preselector comprising a shaft adapted to Y said additional washer, meanscarried by each gear for engaging the adjacent additional washer at a plurality of points and means for simul-' taneously rotating said two=gears in opposite (ii-'- rections.

9. The structure of claim 8 wherein a sleeve is" provided on the shaft on each side of said first washer and wherein said additional washers and gears are mounted on the sleeve.

10. The structure of. claim 8 wherein a sleeve is provided oneach sleeve of said first washer with said sleeves rotatively locked to the shaft but movable lengthwise'thereo, and wherein the additional washers and gears are mounted on said sleeves and wherein means are provided for exerting pressure on said sleeves to tightly jam the first washer therebetween and lock the same.

all/A preselector comprising a-shaft adapted to be turned to a preseleced position, a washer having an outwardly extending finger disposed on said shaft and rotatable around said shaft, a sleeve on each side of-said washer rotativelylocked on each side of said first washer, said sleeve washers having fingers extending toward the first washer finger and adapted to engage therewith after predetermined angles of lost motion, means mounted on each sleeve on the outer side of each of said sleeve washers, said means being freely rotatable on each sleeve and having fingers adapted to engage the fingers of said sleeve washers after predetermined lost motion angles, means for simultaneously rotating said first named means in opposite directions, and means for forcing said sleeves toward each other'to tightly clamp said first washer.

12. The structure of claim 11 wherein said second named means comprises a gear on the outer side of each of said sleeve washers.

13. A preselector comprising a shaft adapted to be turned to a preselected position, a washer having an outwardly extending finger rotatively mounted on said shaft, a second washer disposed on each side of said first washer and freely rotatahle around said shaft, and each second washer each gear carrying a finger adapted to engage the adjacent econd washer finger after predetermined lost motion, and a pair of racks meshin enemas,

to said shaft but movable lengthwise, a sleeve washer freely rotatable on each sleeve disposed with said gears and adapted to turn them simultaneously in opposite directions upon movement of said racks.

14. A preselector comprising a shaft adapted to be turned tofa preselected position, a washer having an outwardly extending finger freely rotatable onsaid shaft, a sleeve on each side of said washer rotatively locked to said shaft but longitudinally movable, a sleeve washer freely rotatable on each sleeve disposed on each side of said first washer, each sleeve washer having a finger adapted to engage the first washer finger after-predetermined lost motion, a gear freely rotatable on said sleeve mounted on the outer side of each sleeve washer, and each gear having a finger adapted to engage the adjacent sleeve washer finger after predetermined lost motion, a pair of racks operating as a unit meshing with said gears and upon movement adapted to turn said gears simultaneously inopposite directions, and means for forcing said sleeves tightly together to clamp said first washer in adJusted position.

15. The structure of claim 14 wherein said last named means is adjustable and includes a spring for urging said sleeves toward each other to permit adjustment of said first washer with respect to said shaft.

16. The structure of claim 14 wherein said sleeves are shouldered to maintain the gear and sleeve washer against lateral movement.

, EDWARD J. MASTNEY. 

